Alarm system and method for detecting proximity of an object to electrical power lines
First Claim
1. A system for detecting the proximity of an object to an alternating current power electrical line which creates a resulting electric field, said system comprising a receiver antenna device capable of receiving a current by capacitive effect and wherein the intensity of the current is a function of the distance separating the receiver antenna device from the said electrical line;
- a measuring and conditioning circuit for converting the said received current to a coded signal, said measuring and conditioning circuit having a low input impedance with relation to a source impedance, whereby the influence of leakage through a supporting structure of the said receiver antenna is considerably reduced; and
alarm means associated with said measuring and conditioning circuit to generate an alarm signal when the said coded signal reaches predetermined stored values.
1 Assignment
0 Petitions
Accused Products
Abstract
An antenna receives, by capacitive effect, a current of which the intensity is a function of the distance separating the antenna from an electrical power line. The other factors that influence the current are fixed, constant or are considered negligible. A measuring and conditioning circuit converts the current at the output of the antenna into a coded signal and transmits this coded signal to a control unit. The control unit compares the coded signal to predetermined values stored therein. Alarms are generated by the control unit when the current from the antenna exceeds the predetermined values.
-
Citations
9 Claims
-
1. A system for detecting the proximity of an object to an alternating current power electrical line which creates a resulting electric field, said system comprising a receiver antenna device capable of receiving a current by capacitive effect and wherein the intensity of the current is a function of the distance separating the receiver antenna device from the said electrical line;
- a measuring and conditioning circuit for converting the said received current to a coded signal, said measuring and conditioning circuit having a low input impedance with relation to a source impedance, whereby the influence of leakage through a supporting structure of the said receiver antenna is considerably reduced; and
alarm means associated with said measuring and conditioning circuit to generate an alarm signal when the said coded signal reaches predetermined stored values. - View Dependent Claims (2, 3, 4, 5)
- a measuring and conditioning circuit for converting the said received current to a coded signal, said measuring and conditioning circuit having a low input impedance with relation to a source impedance, whereby the influence of leakage through a supporting structure of the said receiver antenna is considerably reduced; and
-
6. A method of detecting the proximity of an object to an electrical line having an alternating voltage creating a resulting electrical field, said method comprising the steps of receiving by capacitive effect a current of which the intensity is a function of the ditance separating a receiver antenna device from the said electrical line;
- measuring the intensity of the said received current by a measuring and conditioning circuit having a low impedance as compared to a source impedance whereby the influence of leakage through a supporting structure of said receiver antenna is considerably reduced;
conditioning said received current to provide a coded signal for transmission to a master control station;
analyzing said coded signal in said master control station whereby to compare said signal to predetermined stored values; and
triggering alarm means if the coded signal contains information requiring an alarm to be triggered. - View Dependent Claims (7, 8, 9)
- measuring the intensity of the said received current by a measuring and conditioning circuit having a low impedance as compared to a source impedance whereby the influence of leakage through a supporting structure of said receiver antenna is considerably reduced;
Specification